Car with a vessel for the conveying of hot substances, particularly molten pig iron

ABSTRACT

The refractory lined vessel is elongated and carried by wheeled bogies to be tiltable about a horizontal axis, and includes the improvements, severally and in various combinations, that the vessel shell is bulged and the lining is thickened opposite the opening, preferably over at least 40 percent of the length of the vessel and about half of its peripheral extent, producing a longer lived vessel and one which is cheaper and more readily manipulated in respects set forth in detail.

1 United States Patent 1151 3,661,374 Van Wierst [4 1 May 9, 1972 54] CAR WITH A VESSEL FOR THE 1561 1 References i d CONVEYING OF HOT SUBSTANCES, UNITED STATES PATENTS PARTICULARLY MOLTEN PIG IRON 810,301 1/1906 Von Philp ..266/39 [72] inventor: Wilhelmus Lambertus Van Wierst, Santl995l66 3/1935 Astron? "105/270 00" Netherlands 2,089,l 8/1937 Bugatt1.. ..105/183 p 2,151,391 3/1939 Pugh ..105/270 [73] Assignee: Koninklijke Nederlandsche Hoogovens En 2, 2 H "2 4 Staal Fabrieken N.V., Djmuiden, Nether- 3,013,789 12/1961 Sayre etal- 266/36 lands 3,331,681 7/1967 Mobley 266/34 1,488,436 3/1924 Pugh 266/39 1 Hedi 1969 1,815,605 7/1931 Allen 266/39 [2 N0: Munford R Primary E.\'nminerGerald A. Dost Foreign Application Priority Data Attorney-Hall & Houghton Oct. 7, 1968 Netherlands ..6814343 [57] ABSTRACT 52 us. 01 ..266/39, 105/265, 105 271, The refractory lined vessel is elongated and carried y 266/39 wheeled bogies to be tiltable about a horizontal axis, and in- [511 Int Cl czlc cludes the improvements, severally and in various combina- 58] Field 34 R tions, that the vessel shell is bulged and the lining is thickened opposite the opening, preferably over at least percent of 105/265 E the length of the vessel and about half of its peripheral extent,

producing a longer lived vessel and one which is cheaper and more readily manipulated in respects set forth in detail.

6 Claims, 2 Drawing Figures PATENTEDMM 9 I972 3,661,374

INVENTOR ar/4 M116 1.. VAN w/eR ST ATTORNEY CAR WITH A VESSEL FOR THE CONVEYING OF HOT SUBSTANCES, PARTICULARLY MOLTEN PIG IRON This invention relates to a car with a vessel for the conveying of hot materials, particularly molten pig iron, comprising at least two wheel bogies one behind the other in the conveying direction, the longitudinal vessel extending with its longitudinal axis in the same direction and having an outer shell internally lined with refractory bricks, which vessel is tiltable about its longitudinal axis, is supported by the bogies and is provided about in the center and, in the position for conveying, in the upper part thereof, with an opening.

Such cars, often called moving mixers, hot metal cars or, in view of the shape of the vessel, torpedo cars, are used quite often for the conveying of pig iron from blast furnaces to steel works. Usually this conveying takes place over rails, although the invention could also be applied to such cars for road transport.

An ancillary task of such cars, from which the name mixer originated, is the possibility to allow the pig iron to become somewhat more homogeneous before being processed further in the steel works. By the large volume of such cars, which could take up quantities of molten iron up to to 350-450 tons, it is possible to homogenize large quantities of pig iron simultaneously therein. Moreover it is often the practice to add sub stances such as flux additions to the pig iron in the car vessel or to take steps to desulphurize the iron in said vessel on the car.

In view of the above it will be clear that the tendency is to increase the capacity of such cars more and more. However, this makes it the more necessary to pay the greatest possible attention to the structure of such cars, also in order to lower the costs of investment and maintenance per ton of hot substance such as iron.

One factor which could raise such costs considerably is that, as the vessels are given a greater volume, they have to have an increasing strength in order to take up the bending forces in the vessel between its ends occasioned by its weight of the vessel and by the weight of the hot substance therein, so that the structure is reliable, has a long life-time and is not easily damaged.

Another factor is formed by wear. Highest wear on the refractory lining occurs in the ,zone where the jet of the hot substance such as pig iron falls on the bottom of said lining during filling of the vessel. The hot substance impinges on the bottom of the vessel and splashes around in this central zone. On the spots on which it splashes there are stresses in the brick lining, occuring suddenly and in small and restricted areas. Moreover the jet has the tendency to course considerable wear by erosion to the lining in the small zone where it impinges thereon. This local'wear often is for the greater part responsible for the relatively short length of time during which the vessel can be used without considerable repair and maintenance.

The present invention aims at removing the objections of such known vessels and cars, which could bar the development of such vessels of larger volumes.

ln this respect it is proposed according to the invention to give to the outer shell of the vessel diametrically opposite the opening a shape which is bulged outwardly as compared with the general shape of the remainder of the vessel. Preferably this is embodied in such a way that the refractory lining in the zone of this bulging out has a increased thickness.

Thanks to this shape of the vessel it becomes more rigid in structure, so that for the same internal volume it can be designed so that it is lighter in weight. Also the possibility exists that the vessel for the same longitudinal dimensions even obtains a larger internal volume.

Particularly for such vessels of very large dimensions this could give a very important saving in investment costs. Even more important are the savings obtained in maintenance. If the bottom of the vessel is, as mentioned above, according to the preferred embodiment of the invention, thickened opposite the opening, this bottom is allowed to undergo more wear before the entire lining should be repaired or replaced. Moreover during the greater part of the life-time of the lining of such vessel between two major repairs there will be a hollow or pit in the lining opposite the opening made by the jet. Thus, in filling the vessel, the jet of the hot substance will rather early after the beginning of the use of a new lining fall into a pool of such substance instead of on the hard bottom of the vessel. Thus the splashing of the iron will be restricted considerably. Thus the frequent occurence of considerable and locally quite restricted heat stresses in the lining will be avoided to a considerable extent. A perhaps even more important advantage of the fact that the jet of the hot substance in filling falls into a pool of such substance consists in the circumstance that the energy of the jet is distributed over a larger area. This restricts the erosion of the lining in the zone where the jet reaches the bottom.

It is often usual for such cars to apply additional splash shields nearto and on the outside of the filling opening. Such provisions tend to displace the center of gravity of the vessel so that it is no more in the longitudinal axis thereof. This means that the driving means for rotating the vessel in order to empty it should be heavier and should have more power than would be necessary, as the driving means should also give torque for taking up the unbalance of the vessel during the emptying. When applying the invention, the bulged out part more or less forms a counterweight against such eccentricity. This decreases the unbalance of the vessel and so the driving means could be lighter. It is even possible according to the invention to choose the shape and the amount of bulge such that the vessel with all tiltable parts thereon is essentially balanced with respect to the longitudinal tilting axis. Another advantage of the invention consists in the fact that the outer shell of the vessel has the thickest heatinsulating layer in the zone where the thermal load of the lining is greatest. Thanks to the thicker insulating layer in this zone the temperature distribution in the bulged out part is more uniform, which gives an additional weapon against crushing and breaking out of refractory material.

A favorable amount of bulging out according to the invention is such that the largest bulge of the outer shell is about 7-9 percent of the transverse dimension or diameter of the vessel in this zone.

As to the shape it has appeared that a bulging out is preferable which extends in the longitudinal direction over about 40 percent of the length of the vessel and which extends in the peripheral direction for about half the periphery thereof.

The refractory lining within the outer shell and also within the bulged out part thereof could have different shapes more or less adapted to the shape of the outer shell of the vessel. However, it has appeared that from the point of view of making the brick lining and from the point of view of the relative expansion of the refractory bricks with respect to the outer shell in operation, it is preferable to embody a vessel according to the invention in such a way that the inner shape of the refractory lining consists of a cylinder coaxial to the tilting axis of the vessel, said cylinder being closed at its ends by frustoconical surfaces and is interrupted only in the zone of the opening in the vessel by a somewhat different shape. Preferably the bulged out part is in this combination chosen so as to be shorter in length than the cylindrical part of the refractory lining.

Such a shape of the refractory lining is according to the invention best obtained by giving the bulged out part mainly the outer shape of a downwardly displaced half of a cylinder, having two shell parts joining this half cylinder in the longitudinal direction and merging into the non-bulged part of the outer lining, said two shell parts being substantially part-conical surfaces.

As remarked above, after a short period of use a pit or hollow will be formed in the lining by wear caused by the falling jet of the hot substance. As this hollow or pit as such has a favorable influence upon the conduct of the falling jet, the invention also proposes as a further embodiment to give the lining such a pit or hollow already before putting the vessel into operation when making a new lining, such pit or hollow being positioned diametically opposite the filling opening. This pit or hollow does already at the first filling of the vessel with the new lining fulfil the favorable function as described above for the pit or hollow.

The invention will now be explained in more detail with reference to a preferred embodiment shown in the enclosed drawing. In this drawing:

FIG. 1 shows in longitudinal section and somewhat diagrammatically a car with a vessel according to the invention.

FIG. 2 is a cross-section according to the line II-Il in FIG. 1 on a larger scale.

In FIG. 1 numerals 1 and 2 show somewhat diagrammatically two wheel bogies each with 8 axes, the bogies having upper frames 3 and 4 for supporting the vessel. The bogies and wheels could be of conventional structure, so that a detailed description thereof will not be necessary. The frame structures 3 and 4 have buffer, coupling and drawing means at 5 and 6. At 9 and 10 the frame structures have part-spherical concave supports. Two frame plates 7 and 8, one to each side, are supported through convex part-spherical parts in supports 9 and 10. On such frame plates 7 and 8 bearing the structures 1 l, l2, l3 and 14 all having the same horizontal axis are mounted. In these bearings there are shaft trunnions l5 and 16, mounted rotatably therein and connected to the longitudinal ends of the longitudinal vessel 17.

Driving means 18 shown only diagrammatically and known and usual as such serve to tilt the vessel 17 when it has to be emptied. Such means 18 could include an electric motor, an internal combustion engine or other prime mover, speed reducing means, feed and control means etc. The vessel 17 is provided with an inner refractory brick lining extending between and including two plane end faces 20. The brick lining merges from said faces 20 through conical parts 21 and 22 into a mainly cylindrical intermediary part 23, which is only interrupted and shaped differently in the zone of the filling opening 24. Around the filling opening 24 there is a system of splash shields 25 and other usual parts such as 29, being shown somewhat diagrammatically as being integral with the remainder of the vessel. The entire brick lining is surrounded by a metal outer shell. The splash shields protect this shell against local superheating by spilled liquid metal during filling and emptying of the vessel.

As appears from the drawing the central part of the vessel has in the lower half 26 of the outer shell the shape of a semicylinder, but this is displaced downwardly with respect to the remainder of the outer shell. This part 26 through two shell parts 27 and 28 merges into the remainder of the outer shell. These shell parts 27 and 28 each have substantially the shape of half a frustoconical body. At the parts 26, 27 and 28 of the shell the inner shape of the refractory lining 19 does not follow this shape of the shell, but goes straight on as a cylindrical body, so that this lining in the central part is thicker than in other zones in the vessel 17. It is possible as shown in FIG 2 to make a pit or hollow 30 beforehand in the bottom of the lining immediately below the opening 24. The function thereof is explained amply above.

It will be clear that within the scope of the appended claims many variations of the shape of the vessel are possible when applying the invention. So it would be possible to have the vessel extend downwardly further than shown in the drawing, so that the inner useful volume of the vessel is increased even further.

The vessel according to the invention could be applied for molten pig iron, as a mixer car and for conveying and/or desulphurizing thereof, but also for the conveying of many other very hot substances such as other molten metals.

Iclaim:

l. A car with a vessel for the conveying of hot substances, in particular molten pig iron, comprising at least two wheel bogies one behind the other in the conveying direction, the longitudinal vessel extending with its longitudinal axis in the same irection and having an outer shell internally lined with refractory bricks, which vessel is tiltable about its longitudinal axis, is supported by the bogies and is provided about in the center and, in the position for conveying, in the upper part thereof, with an opening, characterized in that the outer shell has a shape diametrically opposite the opening, which is bulged outwardly as compared with the general shape of the remainder of the vessel, and that diametrically opposite the opening in the vessel a hollow or pit is present in the refractory lining.

2. An improved car for storing, conveying and dumping hot molten metal, the car comprising:

a. at least two wheel bogies one positioned behind the other in the conveying direction, and

b. an elongated vessel tiltably supported by said wheel bogies and having an outer shell internally lined with refractory brick and an opening therein located in a region which lies in the upper central portion of the vessel in the conveying position of the vessel,

said car being improved in that:

c. said outer shell has a zone diametrically opposite said opening, which is outwardly deflected or bulged as compared with the general shape of the remainder of the vessel, and

d. said refractory lining has a thickness in said outwardly bulged zone only which is greater than its lining thickness in any other parts of said vessel.

3. An improved car as claimed in claim 2, wherein:

c. said outwardly bulged zone extends longitudinally over about 40% of the vessel length, peripherally over about half the periphery thereof, and outwardly to a maximum depth of about 7 to 9 percent of the transverse dimension of the vessel at said zone.

4. An improved car as claimed in claim 2, wherein:

e. said refractory lining has an internal surface which is substantially cylindrical and coaxial with the tilting axis of the vessel except at the region of said opening, and which is closed at its ends by frustoconical surfaces, and

f. said outwardly bulged zone is shorter in longitudinal extent than said cylindrical part of said internal surface.

5. An improved car as claimed in claim 2, wherein:

e. the extent of the bulging referred to in clause (c) and the relative thickness of the lining referred to in clause (d) are so proportioned with respect to the remainder of the vessel and parts tilted therewith as to substantially rotationally counterbalance the vessel for tilting about said tilting axis.

6. An improved car for storing, conveying and dumping hot molten metal, the car comprising:

a. at least two wheel bogies one positioned behind the other in the conveying direction, and

b. an elongated vessel tiltably supported by said wheel bogies and having an outer shell internally lined with refractory brick and an opening therein located in a region which lies in the upper central portion of the vessel in the conveying position of the vessel,

said car being improved in that:

c. said outer shell has a zone diametrically opposite said opening, which is outwardly bulged as compared with the general shape of the remainder of the vessel,

d. said refractory lining has a thickness in said outwardly bulged zone which is greater than its thickness in other parts of said vessel, and

e. said refractory lining diametrically opposite to said opening is formed with a hollow or pit therein. 

1. A car with a vessel for the conveying of hot substances, in particular molten pig iron, comprising at least two wheel bogies one behind the other in the conveying direction, the longitudinal vessel extending with its longitudinal axis in the same direction and having an outer shell internally lined with refractory bricks, which vessel is tiltable about its longitudinal axis, is supported by the bogies and is provided about in the center and, in the position for conveying, in the upper part thereof, with an opening, characterized in that the outer shell has a shape diametrically opposite the opening, which is bulged outwardly as compared with the general shape of the remainder of the vessel, and that diametrically opposite the opening in the vessel a hollow or pit is present in the refractory lining.
 2. An improved car for storing, conveying and dumping hot molten metal, the car comprising: a. at least two wheel bogies one positioned behind the other in the conveying direction, and b. an elongated vessel tiltably supported by said wheel bogies and having an outer shell internally lined with refractory brick and an opening therein located in a region which lies in the upper central portion of the vessel in the conveying position of the vessel, said car being improved in that: c. said outer shell has a zone diametrically opposite said opening, which is outwardly deflected or bulged as compared with the general shape of the remainder of the vessel, and d. said refractory lining has a thickness in said outwardly bulged zone only which is greater than its lining thickness in any other parts of said vessel.
 3. An improved car as claimed in claim 2, wherein: e. said outwardly bulged zone extends longitudinally over about 40% of the vessel length, peripherally over about half the periphery thereof, and outwardly to a maximum depth of about 7 to 9 percent of the transverse dimension of the vessel at said zone.
 4. An improved car as claimed in claim 2, wherein: e. said refractory lining has an internal surface which is substantially cylindrical and coaxial with the tilting axis of the vessel except at the region of said opening, and which is closed at its ends by frustoconical surfaces, and f. said outWardly bulged zone is shorter in longitudinal extent than said cylindrical part of said internal surface.
 5. An improved car as claimed in claim 2, wherein: e. the extent of the bulging referred to in clause (c) and the relative thickness of the lining referred to in clause (d) are so proportioned with respect to the remainder of the vessel and parts tilted therewith as to substantially rotationally counterbalance the vessel for tilting about said tilting axis.
 6. An improved car for storing, conveying and dumping hot molten metal, the car comprising: a. at least two wheel bogies one positioned behind the other in the conveying direction, and b. an elongated vessel tiltably supported by said wheel bogies and having an outer shell internally lined with refractory brick and an opening therein located in a region which lies in the upper central portion of the vessel in the conveying position of the vessel, said car being improved in that: c. said outer shell has a zone diametrically opposite said opening, which is outwardly bulged as compared with the general shape of the remainder of the vessel, d. said refractory lining has a thickness in said outwardly bulged zone which is greater than its thickness in other parts of said vessel, and e. said refractory lining diametrically opposite to said opening is formed with a hollow or pit therein. 